A Low-Noise X-Band Radiometer Using Maser
- 1 April 1961
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Proceedings of the IRE
- Vol. 49 (4), 768-778
- https://doi.org/10.1109/JRPROC.1961.287847
Abstract
A low-noise X-band radiometer, using a ruby maser preamplifier in radio astronomy measurements, is discussed. The radiometer uses a reflection-cavity maser with voltage-gain bndwidth products as high as 300 Mc at 4.2°K. Less than 1 per cent short-term gain instability and dependable performance are obtained. A system noise factor (excluding antenna spillover) of 0.6 db 43°K) has been obtained. The system bandwidth is limited to 8 Mc by the intermediate frequency bandwidth, with maser bandwidths of 20-30 Mc available. RMS noise fluctuations of approximately 0.01°K with a 12-second integration time and 0.007°K with a 42-second integration time are obtained. Gain instability of 0.6 per cent up to 10 minutes and 2 per cent up to 30 minutes has been measured. Electrical and mechanical features as well as measurement and operational techniques are described. Performance data and radio astronomy observations are discussed.Keywords
This publication has 8 references indexed in Scilit:
- Measurement of Microwave Radiation at ~3.45 CM from the Planetary Nebula NGC 6543.The Astronomical Journal, 1961
- Recent developments and observations with a Ruby Maser radiometerIEEE Transactions on Antennas and Propagation, 1961
- Radio Detection of the Planet SaturnNature, 1960
- Silvered Ruby Maser CavityJournal of Applied Physics, 1959
- Ruby as a Maser MaterialJournal of Applied Physics, 1959
- Maser Action in RubyPhysical Review B, 1958
- Considerations in High-Sensitivity Microwave RadiometryProceedings of the IRE, 1958
- The Measurement of Thermal Radiation at Microwave FrequenciesReview of Scientific Instruments, 1946